Liana Vilanova can't even sit up yet, but her father is already cheering his 2-month-old's digital prowess, praising her for interacting with an iPad app.

There are dozens of proud parents sharing their infants' touch screen skills in videos posted on YouTube, ooh-ing and ahh-ing over their kids as they interacted with various apps. Babies are transfixed by iPads, so when the device shuts off or is taken away, YouTube videos show them going into full-fledged tantrum, screaming and crying for the device.

Beth Brooks put an iPad in front of her 10-day-old baby, Alex, to see how he would react.

"I guess I just didn't think it was going to hurt, so why not give it a try," she said. "And he seemed to like it."

The iPad didn't exist until three years ago, so there is no hard data yet on the effects the device might have on a child's development.

But could all of the electronic play hurting kids developing brains -- shrinking their attention spans, stunting their social skills or ruining their eyesight?

The Klaus family of Whitehouse Station, N.J., is a very modern family. Devon, 9, Delaney, 7, and Dalton, 4, are savvy digital divas, fluent in iPhone and iPad apps.

"From a distraction perspective, if we go out to eat, which we never do, and they are out of control, we can whip [the devices] out and they will be completely distracted until the food arrives," said their mother, Sharla Klaus.

ABC News wondered what would happen if the Klaus kids would go iPad- and iPhone-free for a month, quitting cold turkey -- no devices for 31 days.

"That means you have to entertain yourself outside or in the playroom," Sharla Klaus told the kids.

The girls were left to play with their analog toys and had to resort to imaginary play. At one point, Devon and a friend played with a pretend iPad.

Perhaps not surprisingly, the Klaus kids fought a lot more without the devices to occupy them, but some child psychologists said those sibling squabbles are healthy socialization.

At Barnard College's renowned Center for Toddler Development, child development experts invited "Nightline" behind a two-way mirror where they were observing several young kids and monitoring their reactions to traditional toys versus an iPad, taking note of how the kids reacted after the iPad was taken away.

The center tested for "distractibility" by having researchers call out the names of the children who were playing with iPads and noted how readily the children responded. Many of the kids were so zoned in on the apps they were playing with, they didn't respond to the researchers at all.

The only toddler who managed to resist the iPads' magnetic pull was a little girl named Viv, who never fully tuned out her environment. She had a full conversation with a researcher while creating a make-believe world of her own.

But once the iPads were confiscated, the researchers believed the toddlers transformed into more verbal, more social and more creative creatures.

Tovah Klein, the director of Barnard's toddler center who specializes in toddler social and emotional development, said the kids were much more active when the iPads were taken away.

"You see how much their vocabulary has gone up and they are talking to each other," she said.

Researchers said imagination needs to be exercised like a muscle in order for creativity to be developed. Over time, children's play became more elaborate and three-dimensional.

Klein said the more parents use iPads, smart phones or similar devices to calm their kids down, the less likely the kids are to learn how to calm themselves down naturally. In other words, if kids are constantly pacified with an iPad, they won't be learning the skills to come down from a tantrum.

Studies show that hours and hours of screen time doesn't do any real harm to a kid's eyesight. But it is associated with behavioral problems down the road, which is why the American Academy of Pediatrics discourages "passive screen time" for kids under age 2.

But tablets are not passive, they are interactive, and that's the intriguing twist. In fact, a recent report from the Millennium Cohort Study, a long-term research project in England that has been following the lives of 19,000 children born in 2000 and 2001, showed that toddlers do learn better from interactive media.

Sesame Workshop, the non-profit organization behind "Sesame Street," has been developing educational apps designed as interactive.

"I'm trying to create content to engage you to interact with your child and so you can extend the learning," said Rosemari Tuglio, the vice president of education and research for Sesame Workshop.

Tuglio said the apps don't just teach letters and numbers, there is more social interaction with characters like Elmo.

As for the Klaus girls, they were thrilled to be reunited with their digital devices, even though, after a month of electronic deprivation, Devon learned an old-fashioned craft: sewing.

"I had free time to do that, like in the morning I started off doing it," she said. "But now, since I have my iPad, I probably won't do that. But I will still use my sewing machine."